That's pretty much what I mean--Damian's taken to the extreme and hasn't been balanced out. Sure there could be an ordinary kid in there (I wouldn't have guessed the kid who showed up at Dick's circus at 13 would be cloning his best friend a few years later either, but strange things happen in the Bat-verse!) and we can see if Morrisson brings it out or likes him going from weapon to scion of the Wayne family. We've yet to see if he's interested in him being too normal. I would imagine many fans might not be.
I would agree, though, that he doesn't read as an adult in a child's body. I think the "he's a kid and here he is acting like one" is a big part of his character--that's the balance of him, actually, I'd say. It's what allows him to be so violent a lot of the time. Super-competent but with a clear, childish streak. That's different than a child in an adult body. A child with an adult's abilities, yes. Which none of the other kids had. They were more sometimes mature children (but mature in the responsible way for at least some of them) with good abilities that could be molded. Except Dick with his acrobatics, of course, but those kids exist.